1. Technical Field
The present invention relates to the field of infrared communications. More specifically, the invention relates to an infrared communication system including a receiver having multiple photo-sensors.
2. Description of Related Art
A conventional infrared communication system utilizes a wireless optical infrared communication link employing a transmitter to emit optical infrared signals that are received by an infrared receiver. A conventional infrared receiver typically employs a single photo-sensor having an “acceptance cone” to detect the emitted infrared signals. The acceptance cone typically has a wide angle of view. This feature permits the reception of infrared signals even when the transmitter and the receiver are misaligned, thus enabling a broader area of reception.
Several optical link protocol specifications have been developed over the past several years with regards to infrared data communications. The Infrared Data Association (IrDA) has issued the Serial Infrared Link Access Protocol (IrLAP), which defines serial infrared links capable of supporting an optical link with a range of at least one meter. An IrDA serial infrared interface must be able to operate at a minimum signaling rate of 9.6 kb/sec, up to a rate of 4 Mb/s wherein the nominal pulse duration is 125 nsec.
Conventional IR receivers having a wide angle acceptance cone, such as those implemented in accordance with the IrLAP specification, typically sense incoming infrared light within a specified solid angle. In addition, IR receivers also sense light emanating from ambient sources, including electromagnetic waves, sunlight, incandescent lighting and fluorescent lighting. These ambient sources interfere with true optical signals, thus lowering the signal to noise ratio of the communication system. These conditions limit not only the signal to noise ratio, but also reduce the optical link range of the communication system. In addition to the foregoing problems, conventional infrared communication systems typically operate at relatively low speeds. Furthermore, because conventional IR receivers have low sensitivity, conventional IR transmitters utilize transistors having high power output, thus resulting in relatively high power consumption.
Further disadvantages of the related art will become apparent to one skilled in the art through comparison of the drawings and specification which follow.